Feature/mbedtls (#84)

* try to import mbedtls and build it

* add stubs socket class

* some boilterplate, read and write function implemented

* more boilterplate / current error in handshake because no CA cert is setup

* add something so skip ca verification, can ws curl https://google.com !

* cleanup / close implemented

* tweak CMakefiles

* typo in include

* update readme

* disable unittests

third_party/mbedtls/tests/data_files/test-ca.opensslconf

@@ -0,0 +1,70 @@
+[req]
+x509_extensions = v3_ca
+distinguished_name = req_dn
+
+[req_dn]
+countryName = NL
+organizationalUnitName = PolarSSL
+commonName = PolarSSL Test CA
+
+[v3_ca]
+subjectKeyIdentifier=hash
+authorityKeyIdentifier=keyid:always,issuer:always
+basicConstraints = CA:true
+
+[othername_san]
+subjectAltName=otherName:1.3.6.1.5.5.7.8.4;SEQ:hw_module_name
+
+[unsupoported_othername_san]
+subjectAltName=otherName:1.2.3.4;UTF8:some other identifier
+
+[alt_names]
+DNS.1=example.com
+otherName.1=1.3.6.1.5.5.7.8.4;SEQ:hw_module_name
+DNS.2=example.net
+DNS.3=*.example.org
+
+[multiple_san]
+subjectAltName=@alt_names
+
+[hw_module_name]
+hwtype = OID:1.3.6.1.4.1.17.3
+hwserial = OCT:123456
+
+[v3_any_policy_ca]
+basicConstraints = CA:true
+certificatePolicies = 2.5.29.32.0
+
+[v3_any_policy_qualifier_ca]
+basicConstraints = CA:true
+certificatePolicies = @policy_info
+
+[v3_multi_policy_ca]
+basicConstraints = CA:true
+certificatePolicies = 1.2.3.4,2.5.29.32.0
+
+[v3_unsupported_policy_ca]
+basicConstraints = CA:true
+certificatePolicies = 1.2.3.4
+
+[policy_info]
+policyIdentifier = 2.5.29.32.0
+CPS.1 ="CPS uri string"
+
+[fan_cert]
+extendedKeyUsage = 1.3.6.1.4.1.45605.1
+
+[noext_ca]
+basicConstraints = CA:true
+
+[test_ca]
+database = /dev/null
+
+[crl_ext_idp]
+issuingDistributionPoint=critical, @idpdata
+
+[crl_ext_idp_nc]
+issuingDistributionPoint=@idpdata
+
+[idpdata]
+fullname=URI:http://pki.example.com/